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Full text of "Medical Jurisprudence And Toxicology"

714                                              MEDICAL  JURISPRUDENCE

digitalis seeds. Dose, J to 1 grain subcutaneously for a single administration and 1/15 to
1/5 grain subcutaneously for repeated administration.

Digoxin is a crystalline glycoside obtained from the leaves of Digitalis lanata. It is a
pharmacopoeial preparation, known as Digoxinum, which occurs in colourless four or five-
sided tabular crystals, having no odour, but possessing a bitter taste m dilute alcoholic
solution. It is almost insoluble in water and in chloroform, but soluble in dilute alcohol.
The initial dose is 1/60 to 1/40 grain by mouth. The maintenance dose is 1/240 grain
once or twice daily. Intravenously the dose is 1/120 to 1/60 gram. Injectio digoxini (dose,
150 to 300 mininis intravenously) and Tabellce digoxini are the official preparations made
from digoxin.

Symptoms.—The toxic symptoms produced by digitalis are gastro-
intestinal at first, and are then referable to its action on the heart. These
are anorexia, thirst, nausea, vomiting followed by severe abdominal pain
and perhaps watery diarrhoea, vertigo, severe headache, fatigue, malaise,
fainting and oppression in the praecordial region. The pulse is at first
accelerated often due to extrasystoles and then slowed, pulsus bigeminus or
other types of arrhythmias may occur; the rate may fall even to 25 per
minute. The respirations are slow and sighing. The pupils are dilated and
visual derangements, such as dimness of vision and changes in the perception
of colour, are present. These are followed by drowsiness and coma. There
may be delirium or hallucinations and convulsions. The urine may be sup-
pressed in some cases. Death usually occurs from sudden syncope. It may
take place on slight exertion during apparent convalescence.

Fatal Dose.—Uncertain. Thirty-eight grains of the powdered leaves and
nine drachms of the tincture have proved fatal, though recovery has ensued
from much larger doses. One-fourth to half-a-grain of digitalin and one-
sixteenth grain of digitoxin might cause the death of an adult.

Fatal Period.—This varies from three-quarters of an hour to twenty-
four hours, but may last several days.

Treatment.—This consists in the use of the stomach tube, or emetics,
followed by aperients, and the free use of vegetable infusions containing tan-
nin, Tea or coffee may also be given with advantage. Keep the patient
warm and in a recumbent posture, administer atropine, strychnine and other
stimulants and apply sinapism to the chest.

Post-mortem Appearances.—Not characteristic. There may be fragments
t of digitalis leaves in the stomach, which may be found congested and
' inflamed.

Chemical Analysis.—The glycosides may be extracted with chloroform
from the acidified organic material.

Tests.—Digitoxin.—Strong sulphuric acid produces a green colour which
is not affected by bromine water.

Digitalin.—Dissolved in strong sulphuric acid, it forms a yellow colour,
which rapidly changes to blood-red. The addition of bromine water changes
the colour to violet-red. Heated gently with a few drops of a mixture con-
taining equal parts of strong sulphuric acid and alcohol, digitalin turns
yellow-brown. The addition of a drop of a dilute solution of ferric chloride
changes the colour to bluish-green.

Digitonin.—Strong sulphuric acid produces a red colour, which is intensi-
fied by adding bromine water.

Medico-Legal Points.—Poisoning by digitalis is not a frequent occur-
rence. A few accidental cases have occurred from an overdose of one of the
medicinal preparations or from eating the leaves by mistake.

Digitalis is rarely used for suicidal purposes, and has been used only
orice as a homicidal poison, when a homoeopathic physician, La Pomerais,